Flow control plunger assembly



Dec. 22, 1964 SABAKA 3,162,337

FLOW CONTROL PLUNGER ASSEMBLY Filed NOV. 15, 1965 FIGURE l FIGURE 2GEORGE SABAKA mvzrnon BY fiamy/ j), MW

- ATTORNEY United States Patent 3,162,337 FLOW CONTROL PLUNGER ASSEMBLYGeorge Sabalka, RD. 3, Hanover, Pa. Filed Nov. 15, 1963, Ser. No.324,026 1 Claim. (Cl. 222327) The present invention is broadly concernedwith plungers for feeding or expelling material from a container. Thepresent invention is more particularly concerned with a plunger,especially a plunger assembly which is adapted for controlling the flowof viscous, mastic-like or semi-fluid materials such as, for example, acaulking compound from the cartridges or containers in which suchmaterials are sold or dispensed.

Thus, the present invention is more particularly concerned with acaulking gun and cartridge therefor, and relates to a caulking assemblythat utilizes a disposable cartridge having a dispensing spout at oneend thereof and a piston at the other end thereof.

Caulking guns that employ disposable cartridges are Well known in theart and generally comprise a gun which supports the cartridge and whichis provided with a lever actuated plunger that is adapted to engage andmove the cartridge piston of the disposable cartridge toward the spout.Thus, movement of the cartridge piston exerts pressure on the caulkingmaterial within the cartridge and displaces the caulking materialthrough the dispensing spout of the cartridge. However, an annoyingproblem encountered with this type of caulking assembly is that, whenthe assembly is set aside after use or between uses, the caulkingmaterial remaining in the cartridge expands and thus oozes or drips fromthe spout. This is evidently due to the relatively high compressibilityand relatively slow recovery of the caulking material. It might also bedue to some extent, especially with a paper cartridge, to a slightswelling of the cartridge body. The expansion of the caulking material,during use, from the spout builds up pressure in the cartridge withresulting compression of the material which, unless permitted to expandwithin the cartridge, will subsequently expand through the spout.

This is particularly annoying since, when the gun is set aside, thecaulking material or compound which remains in the cartridge oozes anddrips on the table or other support upon which it is placed, creating anuntidy and undesirable situation.

Various expedients have been used heretofore to prevent the caulkingcompound or other semi-fluid material from thus oozing or dripping fromthe spout. For instance, the use of a flexible diaphragm among otherthings have been proposed. However, none of these have provensatisfactory since the diaphragm has a tendency to adhere to thecompound and cannot overcome this adherence sufficiently or quicklyenough to prevent the oozing or loss of compound from the dispensingspout. Moreover, in all cases where such a diaphragm has been employed,no provision has been made for the release of the air which is confinedbetween the diaphragm and the caulking compound so that it becomesextremely difiicult to actuate the diaphragm with any degree ofefiiciency.

The present invention is concerned with a unique caulking assemblywhereby positive control can be exerted on the remaining material withinthe caulking gun when it is not in use to positively control and preventthe flow or seepage of material from the gun. The present invention inparticular comprises an integrated assembly comprising the plunger ofthe gun and the movable piston element of the disposable cartridge.

In essence, the piston element movable within the cartridge is a cuplikecylindrical element, the diameter of which is substantially equivalentto the inner diameter of the disposable cartridge, having sufficienttolerance to 3,152,337 Patented Dec. 22, 1964 permit the piston to movewithin and through the cartridge and to substantially prevent anyleakage of the compound behind the piston. The piston has acircumferential skirt element extending rearwardly substantiallyvertical from about the circumference of the base. The distance that theskirt element of the piston extends from the base element of the pistonmay vary appreciably, but is generally in the range from about A" to /3"to The distance the skirt element extends rearwardly from the base ofthe piston may be varied depending upon related conditions such as uponthe diameter of the base.

In accordance with the present invention, ears or lugs or projectionsextend inwardly from the skirt element of the piston. These may beattached by any means desirable, but are preferably punched lugs or earswhich are secured by punching from the outer surface of the skirtelement of the piston. These extending projections which extend inwardlyfrom the skirt element are sufliciently distant from the flat surface ofthe base of the piston so as to permit engagement of the plunger of thegun as hereinafter described. Generally it is preferred that theseprojections be from to A5" to A" distant or away from the flat surfaceof the base element of the piston.

As pointed out heretofore, the gun is substantially a conventional onewherein the piston of a cartridge is caused to move through thecartridge by a plunger element of the gun which is actuated by a leverand a ratchet assembly. Any type of ratchet assembly may be used as, forexample, one described in US. Patent 2,889,085 issued June 2, 1959;inventor: H. B. Collins; entitled Drive Means for Caulking Gun Plungers.

In accordance with the present invention, the plunger element of the gunis actuated by the ratchet assembly of the gun. This plunger element isa disclike metallic element and contains a number of cuts around theperiphery thereof which are of a dimension or depth to permit thedisclike plunger to pass by the projections of the piston skirt and toseat securely on the base of the piston. Orientation to permit thispassage can be secured by rotating the cylindrical dispensable cartridgeto the desired spot or alignment of the projections with the cuts orindentations. When it is desired that no further caulking is necessary,the handle controlling the plunger rod is rotated disengaging thenotches from the ratchet or plunger rod and, at the same time, movingthe nonindented portion of the plunger edges behind the protruding earsof the piston. A backward thrust can then be exerted on the handle,pulling back the plunger and the piston from the nozzle, therebycreating a positive thrust of air in a negative direction through thenozzle and thereby actually causing the mastic or caulking compound tomove backwardly within the cartridge itself.

The apparatus assembly of the present invention may be particularlyunderstood by reference to the drawings illustrating one embodiment ofthe same. FIGURE 1 shows the gun and the cartridge, and the cartridgepiston and gun plunger within the cartridge in a nonengaged position.FIGURE 2 shows the gun plunger and cartridge piston in a locked orengaged position whereby as a rearward thrust is exerted on the handle arearward thrust will be exerted on the piston by the plunger causthepiston to move away from the cartridge nozzle.

Referring specifically to the drawing, a caulking gun I is shown havingdisposed therein a dispensible cartridge 2 having a dispensing nozzle orequivalent means 3 at the front end thereof. The cartridge 3 ispositioned in caulking gun I in a conventional manner; namely, bythrusting the same rearwardly within housing 4 of gun I and thenpermitting the nozzle 3 to seat in slot 5 and to be locked therein byhousing 6 of the caulking gun. Movable piston element 7 comprising apiston base 8 and a backwardly extending piston skirt 9 is shownapproximately halfway through the disposable caulking cylinder 2 orcontainer 2. Punched inwardly from piston skirt 9 of the piston 7 areprojections 10 which are a distance above or away from piston base 8.The gun plunger element or disc 11 is actuated by means of plunger rod14 having notches 12 and a ratchet assembly 13, in conjunction withlever 21 (not shown in detail), within handle 1. Plunger or disc 14 isshown disposed a distance apart from the piston 7 in a nonengagedposition. Plunger 11- contains'a number of peripheral notches 15 or in-,

dentations which will permit the placing of plunger 11 on piston baseelement 8 of piston'7 by permitting the protrusions or projections 10 topass through the notches --When it is no longer desired to utilize, thegun, gun or plunger rod 14 is rotated by means of handle approximately180. This places the slots 15 in nonalignment with the ratchet in thehandle; This rotative'rnovement disengages notches 12 of gun or plungerrod 14-,from the ratchet assembly andpermits free movementof' theplunger hind projections 10 of the piston skirt.v It is to be noted thatrotation of handle 20 approximately -180..disengages the notches of theplunger rod from the ratchet and, at

the same time, rotates plunger 11 in a manner to seat and narrow nozzleof the material when not in use, thereby preventing hardening of thematerial and subsequent chokingof the nozzle. 7

What is claimed is:

, An assembly whichcornprises in combination, a disposable cylindricalcartridge containing a viscous'material,

rod backwardly' since it is not engaged in the ratchet assembly. j 7

The rotative movement, as-pointed out,-- also places 7 slots 15 of thedisc or plunger 11 in nonaxial alignment with projections 10 of pistonskirt=9, therebyplacing pro jections 10 in direct contact with thebacksurface of plunger 11. e e e Upon exerting a backward thrust on handle20, plunger rod 14 will move freely to the rear, causing plunger 11 tomove to the rear and also causing piston 7 to move toward the rear bymeans of the thrust exerted by the back surfaceofplunger 11 on theprojections 10 of skirt, 9.

This positive-effort and thrust will cause' air to back-1 flow throughnozzle 3, thereby clearing this nozzle of the havinga spout at one endand "an :axially movable piston element at the. other end; and a gunwhich supports the cartridge provided with an axial movableplunger andin-' cluding'a'plunger rod containing indentations about part of itscircumference for meshing with meansffor incrernentally advancing saidplunger; rod and said plunger, said piston element being characterizedby having a piston base and a'circumferentially backwardly extendingpiston skirt, said pistonskirt' containing projections and perforatio nsboth formed by portionsjof the skirt being punched V withsaidprojections extending inwardly from said piston mastic or caulkingcompound and causing the same to.

move into the main body of the cylinder. This has two extremelydesirable features.

terial or caulking compound, and also effectively clears nozzle 3 ofcaulking compound and mastic material. ;As

is well known in the art, the retention of arelatively small amount ofcaulking compound in a narrow area such as a nozzle 3 causes thismaterial to harden and, in many instances, makes it extremely diificultto use the cartridge subsequently. V r a 'The number of projections andslots on the piston and plunger may be varied appreciably,dcpending uponthe other features of the assembly. However, it is preferred that thenotches and slots approximate from about 2' to 6, preferably about 3.The exten'tto which the projections v In the first place, it preventsoozing and seeping of the mastic ma- 5 skirt, distant from said pistonbase; said plunger being characterized by containin'gfa number ofindentations about itsperiphery so as to permit said plunger to passby'said projections and bear against said piston base, meansfonrotatingsaid plunger and said plunger rod so 'as to secure a no nalignm'entbetween. said indentations and said projections and to secure ademeshing of the indentations of'the plunger rod from said means forincrel mentally advancing said plunger rod and said plunger,

whereby"as"said plunger is withdrawn rearwardly, said projections bearagainst the top surface of said plunger causing said piston element'tomove rearwardly within are extended within the skirts of the piston maybe .also

varied appreciably; They should be of sufiicie'nt length so as to havethe necessary mechanical strength to avoid shearing of the same uponexerting a backward thrust upon the'piece which is interlocked. FIGURE'2, as pointed out heretofore, shows the plunger 11 engaged in piston 7be- "said cartridge causing; air to backflow through said spout. m

References Cited by th'eExaminer UNITED STATESPATENTS RAPHAEL'M. LUPO,Primary Examiner; i

Lou s DEMBO, Examiner;

